Method and system for measuring the dimensions of a three-dimensional object

ABSTRACT

A method and device for measuring the dimensions of a three-dimensional object (8) wherein the object is placed in a measuring corner which defines an x, y, z three-dimensional coordinate system, and wherein in connection with each coordinate at least one graded scale means (9) is provided. Optically machine-legible codes are provided along the respective graded scale means or a combined code for two axes together is provided in at least one of the coordinate planes. The projection of the objects on each coordinate (x,y,z) is registered by means of an opto/electrical reader ( 1,2) and the signals from the reader are fed into a computer (4) which, on the basis of the received signals for each coordinate, calculates and prints out, or displays, the characteristic data of the object. It can be used, for example, for freight charge calculations relating an object.

The present invention relates to a method for measuring diamensions of athree-dimensional object, wherein said object is placed in a measuringcorner which defines an x, y, z three-dimensional coordinate system, andwherein in connection with each coordinate at least one graded scalemeans is provided. Further, the invention relates to a system formeasuring dimensions in this way, wherein the corner is formed by twovertical walls, optionally one vertical wall and a graded scale means,which are positioned at mutual angle of 90°, and a horizontal base onwhich the object is placed when being measured.

Volume measuring devices of this kind are previously known, and U.S.Pat. No. 2,736,095, in particular, teaches one such device where twovertical walls arranged so as to be mutually 90° apart forming a cornertogether with a conveyor upon which an object is placed. Scale means aredisposed in the form of a plurality of graded markings on the two wallsso that, for example, the length of the object can be measured alongsaid graded markings by means of a set square whilst said object liesadjacent to one of said walls where curves indicate a defined surfacearea. Alternative solutions are also found in U.S. Pat. No. 4,268,967.One disadvantage with the known systems is that to take the desiredmeasurements along the coordinates is time-consuming, whereafter thevolume must be calculated either by using tables or a separatecalculator into which the measured coordinates are entered. For therational handling of objects such as packages which are to be sent, forexample, by mail or another form of transport, it is essential to takereadings of and calculate the desired data for the package as quickly aspossible.

According to the invention, this is done by using partly known means,per se, and the method is characterized in that the incremental markingson the scale respective means are provided with an opticallymachine-legible code, for example, a bar code, which represents arespective distance from the origin of the coordinate system, that thecode for each coordinate is read by an optical/electrical reader by saidreader being moved towards or caused to detect a coded marking at therespective coordinate lying freely nearest to the object, wherein saidmarking contains both information regarding metric dimension and alsothe perspective coordinate axis, that the code is registered by thereader, that the code registered by the reader is converted to anelectrical signal which is signal-processed on the basis of the receivedsignal for each coordinate, and to calculate and provide a print-out ordisplay of characteristic data of the object, for example, measured x, yand z coordinates, length, width and height, the calculated cubicalvolume, greatest length plus circumference, etc.

A combined optically machine-legible code can, to advantage, be providedfor the respective measuring points in at least one of the planes xy, xzor yz of the coordinate system. Thus, in effect, only two readings areneeded to calculate said exemplary disclosed characteristic data of theobject. When the method is used for calculating the freight charge, itis expedient to have a computer calculate said freight charge on thebasis of said calculated, characteristic data, possibly also the weightof the object.

The system according to the invention is characterized in that thegraded scale means has an optically machine-legible code on itsrespective graduated markings, for example, bar code, that anopto/electrically functioning code reading device is provided, forinstance, a manually operated bar code reader, for reading the codewhich is closest to the respective coordinate, wherein said marking codecontains both information regarding metric dimension as well asrespective coordinate axis, and that the code reading device isconnected to a signal processor for calculating and displaying, forexample, by means of an optical display or printer, the characteristicdata of the object, for example, x, y, and z coordinates, the cubicalvolume of the object, the greatest length plus circumference, freightcharge, etc, or for data transmission via signal cable to a anothersignal processor in electronic form for further processing, forinstance, automatic invoicing.

According to a further embodiment of the system, said graded scale meansis associated with a weighing scale on which the object is placed duringthe measuring of its dimensions, and a means is provided fortransferring the weight data of the object to said computer or saidother computer.

The invention shall now be described in more detail with reference tothe enclosed drawings:

FIG. 1 depicts the system according to the invention.

FIG. 2 illustrates a scale means according to the invention.

FIG. 2A is an enlarged view of section 2A in FIG. 2.

FIG. 3 depicts a three-dimensional x, y, z coordinate system with theuse of scale means as shown in FIG. 2.

FIGS. 3A, 3B and 3C are enlarged views of sections 3A, 3B and 3C,respectively, in FIG. 3.

FIG. 4 shows the use of a measuring corners as shown in FIG. 3 formeasuring the dimensions of a package.

FIG. 5 shows the section V in FIG. 4.

FIG. 6 illustrates the use of a combined optically machine legible codewhich represents two coordinates at respective measuring points in oneof the measuring device planes, in FIG. 6 the yz plane.

FIG. 6A is an enlarged view of section 6A in FIG. 6.

FIG. 7 shows the measuring of the yz coordinate of a corner of anobject.

FIG. 8 shows the section VIII in FIG. 7.

FIG. 9 shows an alternative solution to that which is shown in FIGS. 3and 4.

In FIG. 1, block A illustrates a measuring corner, which, in effect, isa mechanical construction where the respective coordinates x, y and zare provided with markings which represent the distance from origin 0.These markings can expediently be made of bar codes, although this isnot considered to be limitative for the concept of the invention. Inblock B, a bar code reader 1 is shown with a decoder 2, wherein the barcode reader, by means of its detecting beam, intercepts the bar codes atthe desired point and transfers these to decoder 2 which converts thedetected signals into electrically legible signals which via aconnection 3 are transferred to a computer 4 which forms part of a blockC. The data may alternatively be transferred via a signal cable to asecond computer in electronic form for further processing, for example,automatic invoicing. In block C there is also a data display 5 ifnon-permanent display is desired, and optionally a printer 6 if apermanent read-out is desired, relating to the characteristic data ofthe object which is to be placed in the measuring device in block A. Itwill thus be understood that between block A and block B, the measuringof the object takes place by means of optically reading its dimensionsin x, y and z directions. Transfer of information from block A to blockB thus occurs optically, as disclosed by reference numeral 7. The objectwhich is to be measured in block A has been given the reference numeral8 and is indicated in dotted lines.

In FIG. 2 a measuring device 9 is shown in the form of a traditionalmeter rule. In addition to the measurements being marked by numbers onthe meter rule, they are also, in the example shown, marked by barcodes. By reading the bar codes at a point on the meter rule, it is alsopossible to read the measurement which is also marked by numbers at thispoint on the meter rule. In FIG. 2A, A thus represents the coordinateZ25 in the bar code, B represents Z26 in the bar code, and C representsZ27 in said bar code.

In the solution in FIG. 3, a measuring corner is provided as is alsodisclosed in block A in FIG. 1. Three scale means or meter rules areprovided as is explained in connection with FIG. 2, in such a way thatan axis intersection or corner is thereby formed. In FIG. 3, the x, y,and z directions are more closely defined. In order to avoid confusingx, y and z when making measurements, it would be expedient to usedifferent meter rules in the three different directions. The meter rulescan be positioned in such a way that they indicate the distance toorigin. On FIG. 3, A indicates X7 in the bar code, B indicates X8, CZ25, D Z26, E Y31 and F Y30 in the bar code. Thus, for example on themeter rule which points in the z direction, the code Z25 will be foundin bar code at a distance of 25 cm from the origin. At the same distance25 is marked is legible numbers on the meter rule.

In FIG. 4, it is illustrated how a package can be measured by placing itinnermost in the measuring corner. Consider the package 8 projectednormally on each of the three axes in the coordinate system. It isthereby made possible to read the. dimensions of the package in the x,y, and z directions by reading the bar code at the points where theprojection of the package intersects the three axes. In order to readthe bar code said bar code reader 1 is used which, via a cable 1', islinked to a decoder 2, said decoder 2 communicating via an electricalconnection 3 with a computer 4, see FIG. 1. The section V in FIG. 4 isshown in more detail in FIG. 5. This is a section of the point at whichthe dimension is measured in the y direction. The correct reading herewill be 42 cm. It will immediately be understood that the x and ydimensions are read in a similar way as described hereinabove for the zdimension in connection with FIG. 4.

By projecting the package 8 on a plane instead of on a line, it ispossible to read two coordinates by means of one single reading by usingthe bar code reader 1. In FIG. 6, this is drawn for the yz plane. Aplate or wall 10 is provided with bar codes arranged in a grid. Anenlarged section of the grid is shown in FIG. 6A. The bar code in asquare indicates the distance of that square from the origin along the yaxis and the z axis, respectively. Thus, bar code A in FIG. 6A indicatesthe coordinate y=18 and z=22, whilst bar code B indicates y=18, z=21.

As another example, it can be mentioned that with a distance of 25 cmfrom the origin along the y axis and 30 cm from the origo along the zaxis, an indication of "Y25 Z30" in bar code is obtained. It would alsobe expedient for these measurements to be marked in legible numbers inthe relevant square in the grid.

In FIG. 7, a practical utilization of the solution in FIG. 6 is shown inmore detail where the package is measured by readings being made in they and z direction in one operation, in addition to the x direction, bythe y, z direction being read by making a reading of the bar code whichis found at the point where the corner of the package is projected intothe yz plane. In the example shown, the correct coordinate for the xzplane will be y=19, z=25, see FIG. 8.

Most bar code readers on the market today are based on HeNe lasers, andthese bar code readers generate a clear red beam of light which showswhere reading is made. The majority of bar code readers on the marketare activated by applying pressure to a "pistol trigger". The light beamis thus switched on. When the code is read an acoustic signal is given,and the light beam is extinguished. It is not switched on again beforethe "trigger" is pressed once more. The bar code readers function inthis way, or can be configured so as to function in this way.

Provided that the bar code reader functions in this way, there will be agood visual/acoustic control of the reading having been made, and thatthe correct code has been read.

However, bar code readers without visible light may also be used, forexample, camera-based readers, but these are more difficult for theoperator to use.

In the system that has been described in connection with FIG. 1, a meansfor weighing the object may optionally be included, symbolized by blockD. Block D can contain a known weighing scale 11, know per se, whichcommunicates with block C via a signal path 12. In a case of this kind,it would be expedient to mount the bar code rulers on the weighing scale11, and possibly subtract the weight of these when weighing the object.If the weight is also of significance in the calculation of the freightcharge of the object, it would be desirable to also have the weight ofthe object fed into the computer 4 together with the othercharacteristic data of the object 8 which have been registered by meansof the reader 1. It is desirable for the xy plane to be in the form of aplatform for the object 8 which communicates directly with a weight cellin the weighing scale 11. This is symbolized by the dotted arrows 13between block A and block D.

The software which is put in the computer 4 coordinates the data whichhave been fed in and any additional data entered via a keyboard 14, seeblock C. Additional data of this kind can, for example, be linked todistance of transport, transport means, delivery time, and other freightcharge related data. Other relevant data relating to the package(customer number of the sender, package number, addressees postal code,etc.) are often already found in bar code on the package, and can oftenbe read by the same bar code reader.

It will thus be understood that the greatest costs for the developmentof the present system will be incurred by the construction of a"measuring corner" which describes the three measuring coordinates, aswell as by the development of suitable software.

By having all dimensions on a meter rule or gauge plate are marked inthe bar code as well as in legible text, it is also enabled manualreading and key entry via the keyboard to the computer 4, for example ifthe bar code reader 1, for one reason or another, is defect.

One advantage of the invention is that both bar code readers andcomputers of the type needed for the implementation of the invention canbe bought as cheap standard components. The registration system ofpackage data often consists of a weighing scale and a bar code readerlinked to a computer. Extra costs for the introduction of volumemeasurement will thus merely be an up-date of software and the provisionof bar code rulers in a system of coordinates.

It is obvious, moreover, for a person skilled in the art thatinformation regarding the axis which is to be measured can be coded inother ways than those which are shown and described in connection withthe preceding specification. As an example numerically disclosed data,OCR lettering, can be mentioned. It is also possible to use another formof resolution or denoration. A resolution of less than 1 cm is notpractical in the embodiment which is shown in FIGS. 6 and 7. However, aresolution of 1 cm will normally be more than sufficient. A resolutionof more than 1 cm, for example, 2-3 cm will usually be sufficient.

Even though in the examples rectangular packages only are shown, itwill, of course, also be possible to use the present invention forpackages which have an uneven outer contour. The operator is thenobliged to project or aim the package in towards the meterrule/measuring plate in order to read the greatest dimension along therespective axes.

Although in the present specification bar code readers, in particular,are described, it will immediately be understood that the presentinvention shall not be considered restricted to the use of these, butthat it would be possible to use other types of optical readers.

It will also be understood that the measuring device itself can beformed in several alternative ways. In principle, it is sufficient tohave two walls at the corner, as one wall can be used to read thedimensions in two coordinate directions. As an alternative to one of thetwo walls, one meter rule can also be provided, as is indicated in FIG.7. However, it will often be practical to have a wall 15 in the xz plane(as the example in FIG. 7 shows with the reference numeral 15 and dottedline).

As an alternative to using a manually operated optical reader 1, it willalso be understood than a fixed mechanical reader unit can be used whichreads all visible codes on the walls of the corner and calculates thecharacteristic dimensions or data of the package 8 on the basis of thecodes which are read in this manner. Thus, it will be the lowestnumerical value along each axis that will be registered. In this case, atotal of three bar code readers will be needed for the x, y and z axes,respectively and a solution as is shown in FIG. 3 or FIG. 4 could besuitable for taking measurements in this way.

FIG. 9 shows an alternative embodiment to that which is shown in FIGS. 3and 4. Here somewhat wider meter rules 9' are used together with astationary bar code reader 15 which is capable of reading bar codes ofdifferent orientations, for example by transmitting two mutuallyperpendicular scanning detecting beams 16 and 17 to detect the x and ycoordinates, respectively, as well the z coordinate for the object 8.Bar code reader and/or control system must be capable of picking out thelowest values which are registered along the different axes and usethese as dimensions of the package.

I claim:
 1. A method for measuring the dimensions of a three-dimensionalobject, wherein the object is placed in a measuring corner which definesan x, y, z three-dimensional coordinate system, and wherein inconnection with each coordinate at least one graded scale means isprovided, characterized in that at the graded markings of the respectivescale means there is provided an optically machine-readable code whichrepresents a respective distance from the origin of the coordinatesystem, that the code for each coordinate is read by anoptical/electrical reader by moving towards or causing the reader todetect a coded marking lying freely closest to the object at therespective coordinate, said marking containing both informationregarding metric dimension and also respective coordinate axis, that thecode is registered by the reader, that the code registered by the readeris converted to an electrical signal which is signal-processed on thebasis of the signal received for each coordinate, and to calculate andprovide a print-out or display of characteristic data of the object orto transmit said data in electronic form to a signal processor forfurther processing.
 2. The method as claimed in claim 1, wherein acombined optically machine-legible code for the respective measuringpoints is arranged in at least one of the planes xy, xz or yz of thecoordinate system.
 3. The method as claimed in claim 2, wherein thecomputer calculates a freight charge for the object, on the basis ofsaid calculated characteristic data.
 4. The method as claimed in claim3, wherein said characteristic data includes a weight of the object. 5.The method as claimed in claim 1, wherein the computer calculates afreight charge for the object, on the basis of said calculatedcharacteristic data.
 6. The method as claimed in claim 1, wherein saidoptically machine-readable code is a bar code.
 7. The method as claimedin claim 1, wherein said characteristic data include measured xcoordinates, measured y coordinates, measured z coordinates, length,width, height, a calculated cubical volume of the object, a greatestlength and circumference.
 8. The method as claimed in claim 1, whereinsaid characteristic data include a freight charge.
 9. The method asclaimed in claim 5, wherein said characteristic data includes a weightof the object.
 10. A system for measuring the dimensions of athree-dimensional object, wherein the object is placed in a measuringcorner which defines a three-dimensional coordinate system, and whereinin connection with each coordinate at least one graded scale means isprovided, and wherein the corner is formed by two vertical walls,possibly a vertical wall and a graded scale means having a mutual angleof 90°, and a horizontal base on which the object is placed when beingmeasured, characterized in that the graded scale means has, at itsrespective graded markings, an optically machine-legible code, forexample, a bar code, that an opto/electrically functioning code-readerdevice is provided, for reading the code which lies close to therespective coordinate, wherein said marking code contains bothinformation regarding metric dimension and respective coordinate axis,and that the code reader device is connected to a signal processor forcalculating and displaying, via an optical display or printercharacteristic data of the object, or for data transmission via a signalcable to another signal processor in electronic form for furtherprocessing.
 11. The system as claimed in claim 10, wherein said gradedscale means is associated with a weighing scale on which the object isplaced whilst its dimensions are measured, and that a means is providedfor transferring weight data of the object to said computer or saidanother computer.
 12. The system as claimed in claim 10, wherein saidcode reader device is a manually operated bar code reader.
 13. Thesystem as claimed in claim 10, wherein said characteristic data includemeasured x coordinates, measured y coordinates, measured z coordinates,length, width, height, a calculated cubical volume of the object, agreatest length and circumference.
 14. The system as claimed in claim10, wherein said characteristic data include a freight charge.
 15. Thesystem as claimed in claim 10, wherein said further processing includesautomatic invoicing.